Discrete - Time Dataflow Models for Visual Simulation in Ptolemy

The Discrete Time (DT) domain in Ptolemy II is a timed extension of the Synchronous Dataflow (SDF) domain. Although not completely backward compatible with SDF, DT keeps most of the desirable properties of SDF like static scheduling, regular/periodic execution, bounded memory usage, and a guarantee that deadlock will never occur. In addition, DT has some desirable temporal properties such as uniformly-timed token flow and causality. This paper will present the semantics and implementation of the DT domain in Ptolemy II. This paper will also present the DT domain working with other domains in Ptolemy II. In particular, it will present applications of DT working with the Graphics (GR) domain for 3D animated simulations. iii ______________________________________________ Acknowledgements I would like to thank my research advisor, Professor Edward A. Lee, for introducing me to this research area. I appreciate all the support and guidance that he has given me. I really enjoyed my meetings with him where we brainstormed through the different twists and pitfalls of research in dataflow computing. I would also like to thank Professor Alberto Sangiovanni-Vincentelli, the second reader of this report. His EE249 class gave me solid background on the different models of computations. I would also like to thank all my colleagues in the Ptolemy group. I really appreciate the help given to me Lastly, I would like to thank my parents for their continuous support and encouragement. This report is dedicated to them.